56 SCISSURELLA. 



S. aedokia Watson. PI. 58, figs. 1, 2, 3. 



Shell depressedly globose, strongly sculptured, with a rather high 

 scalar spire, exserted whorls, a very sharp and expressed carina, a 

 minute tabulated apex, a strong and impressed suture, a tumid base, 

 and a large pervious but half covered umbilicus. Sculpture : The 

 radiating ribs are pretty strong, sharp, and equal above and below 

 the canal. Spirals — the whole surface is closely sharply, and 

 regularly scored with fine threads, which are a little stronger (but 

 not quite so sharp) on the base than above. Color white. Spire 

 high, scalar, each whorl rising and expanding above the suture. 

 Apex very small and tabulated. Whorls 5 ; they slope down flatly 

 (barely convex) from the suture, are very sharply carinated at the 

 canal, the under edge of which in particular is prominent and ex- 

 pressed ; below the canal they contract into the suture ; the base is 

 tumid. Suture strongly impressed and very distinct. Mouth quite 

 round. Outer lip thin, regularly arched. Inner lip on the body 

 thin, and very short, regularly curved throughout, on the pillar-lip. 



Alt. -099 in. ; diam. -09. ( Watson.) 



This species has the strong lamella? of lamellata, A. Ad., from 

 Japan, but these are here still stronger, with a high spire and tumid 

 base. It has some resemblance to Scissurella umbilicata, Jeff, but 

 the spire is much higher, the whorls more exserted and contracted 

 below the canal, and the sculpture is quite different. ( Watson.) 



Off Pernambuco, in 350 fms. ; Nightingale Island, Tristan da Gunha, 

 100 to 150 fms. 



Scissurella cedonia Watson, Challenger Bep. Gasterop., p. 114, t. 

 8, f. 3, 1886. 



S. coronata Watson. PI. 58, figs. 11, 12, 13. 



Shell obliquely discoidal, strongly ribbed and spiralled, flattened 

 above, with the apex rising like a coronet above the flat upper 

 surface of the whorls, a largish very oblique oval mouth and a large 

 funnel-shaped pervious umbilicus. Sculpture : Longitudinals — above 

 the canal the surface is distantly, radiatingly, and curvedly undulated 

 (like a Haliotis), with minute, sharp, close-set threadlets in the 

 intervals ; below the canal there are high, narrow, distant, very 

 curved ribs, which begin feebly below the canal-ridge, and die out at 

 the edge of the umbilicus. Spirals — the old canal rises on a rounded 

 and very prominent ridge, which is perpendicular on the outer and 

 elevated on the inner side ; the canal itself is not depressed, but is 



